Liquid actuated motor



Feb.11,1941. 1 P, E, ASQTGN ETAL 2,231,355

LIQUID ACTUATED MOTOR Feb' 1l, 1941 P. E. ASHTON E-rm. 2,231,355

LIQUID ACTUA'IED MOTOR Filed June 14, 1938 4 Sheets-Sheet 2 Feb.` 11,1941. P. E. ASHTON ETAL LIQUID ACTUATED MOTOR 4 Sheets-Sheet 3 FiledJune 14, 1938 TCRNEY Feb. 11, 1941. P, E, ASHTON ETAL 2,231,355

LIQUID ACTUATED MOTOR Filed June 14, 1958 4 sheets-sheet 4 f M f TTORNEYPatented Feb. 11, 1941 UNITED STATES LIQUID ACTUATED MOTOR Philip E.Ashton and Sidney L. Wolfson, Meriden,

Conn., assignors to The Cuno Engineering Corporation, Meriden, Conn., acorporation of Connecticut Application June 14, 1938, Serial No. 213,583

18 Claims.

Our invention relates particularly to motive devices for self cleaningliquid filters.

The Cuno Patent 1,747,149 shows a multipleplate type lter in a pressurelubricating system with means for automatically turning the plates withrespect to cleaning members upon certain periodic or intermittentchanges of pressure in the system. The Cuno Patent 1,769,502 showsanother filter with liquid actuated means for continually cleaning thefilter while the system is in operation.

Our present invention seeks to provide a motorv device which is reliableand capable of long sustained' use under the `most trying circumstancessuch as in aeroplane engine lubricating systems.

There .are many requirements for such a motive device. It should operateon the usual available oil pressure. The cleaning action should be selfstarting from any position. The iilter should continue to operate for asubstantial period even if the cleaning means becomes disabled. Itshould be compact and capable of quick installation, easy to inspect andeasy to clean. it should be capable of satisfactory operation under thegreatly varying conditions which occur in such systems-such as changesin motor speed, wide temperature changes, changes in viscosity of theoil, and considerable changes in the oil pressure. It should be selflubricating under all circumstances.

It is also desirable that it be capable of replacing existing handturned filters without structural changes to the engine.

Preferably the liquid actuated motor should use the clean liquid whichhas already been ltered. It should require only a small percentage ofthe oil for itspower device or motor and there should be no waste.

It is highly desirable to avoid the necessity for packing or stuflingboxes. There should be means for automatically by-passing the ilter incase it gets clogged. It is also best to avoid external parts orpipe-lines. In order to prolong the useful life of the filter all themovements of the filter and of the motive device should be very slow andyet positive. Although the cleaning action should preferably besubstantially continuous and automatic, it is desirable to provide forturning the filter element by hand in case of emergency and in order totest the lter to see that it will turn.

We have illustrated the invention as applied to the rotatablemultiple-spaced plate type of lter with intervening stationary scrapingor cleaning fingers. It should be understood however that the inventionrelates Ato the genera] construction and to the means for supporting andactuating the movable element of the lilter. In the form shown hereinthe motor which rotates the filter element is mounted in a housing whichalso encloses the control valve mechanism. The lter elements are securedto this housing so that the entire structure may be handled andinstalled as .a single unit. The motor has a reciprocating piston whichturns the Valve back and forth to reverse the direction of pressure onthe piston, without danger of stopping on a dead center.

A spring pressed toggle arm and lever have a lost motion connection withthe valve. A clutch on the end of the filter shaft extension in thehousing is rotated by the action of the piston. All of the moving partsare enclosed .and immersed in oil and parts are so designed that only asmall quantity of oil is required to operate the cleaning motor and eventhat oil is returned to the system. y

Fig. 1 is a side view of a construction involving one form of ourinvention showing in dotted lines the parts of the oil reservoir of anengine with which it would be used.

Fig. 1a is an enlarged fragmentary section showing a detail of theiilter support.

Fig. 2 -is an end view of the ltering device.

Fig. 3 is an end View of the housing which contains all of the movingparts of the liquid .actuated motor for turning the filtering element orthe cleaning element as the case may be, the lter parts being omitted.

Fig. 4 is a longitudinal sectional view of parts of the housing, clutch.and relief valve.

Fig. 5 is a cross sectional view of the liquid actuated motor 'and itsvalve and housing on the plane lof the line 5-5 of Fig. 6.

Fig. 6 is a longitudinal sectional View -oi the same parts on the planeof the line 6 6 of Fig. 5.

Fig. 7 is a view of the inner face of the cover of the housing showingthe attached parts of the motor and its control valve mechanism.

Fig. 8 is an end View, partly in section, looking into the housing andshowing the clutch device, the ycover and attac-hed motor parts beingremoved.

Fig. 9 is an exploded perspective view of the parts of the control valveand its connections.

Fig. 10 is a side view and partial section showing the control valve andits arrangement in the housing.

Fig. 11 is a rear View and section of the control-valve device and itssupport.

Fig. 12 is a sectional view showing the valve in a position reverse tothat of Fig. 5.

`It is desirable that the filtering unit be a multiple spaced plate typehaving a set of plates such as plates I5 and scraper members i6interposed between the plates. One of these sets is rotatable,preferably the plates I5 which are mounted on the rotatable shaft ll.The scraper plates or ngers are mounted on a shaft I6 which may besquare in cross section Where the scrapers are mounted. One of theplates I 5 fixed on the shaft I1 has a bearing in the annular plate I8.The annular plate I9 similarly supports the opposite end of the shaftl1. in the rear part 23 of the head 22 and pass through plates I8, I8'.A nut 20 holds plate I8 on each rod 20. A sleeve 2| is secured to thehead extension 23 and ts into openings 26', 26" in the engine casing. Acollar 2 I carried by the inner end of the filter unit ts into anotheropening in the engine casing leading to the discharge port 21. PassagesI8a extend through the plates of the filter unit. The collar 2l fitssnugly in the engine casing and acts as a support or bearing for theinner end of the rotatable part of the filter unit. The sleeve 2| may beextended beneath the lter unit so as to act as a collector of sludgeremoved from the plates during the filtering operations and thusfacilitate removal of sludge from thengine casing and may have openings2|" for passage of oil to the filter plates.

The hea-d 22 of the filter unit constitutes a housing for the motor andclutch. A cover 24 is suitably secured to the housing by screws or bolts24 and supports the parts of the mo-tor. The unit is lsecured inV placein the engine casing by screws or bolts 22'.

'Ihe motor and clutch are mounted in the chamber 25 in the housing andthe filtering unit extends into a pressure chamber 26 in the oilreservoir which is sealed from the main chamber 28 by sleeve 2 I. Theoil to be filtered is under pressure of the usual oil pump (not shown)and passes into chamber 26 and -then inwardly through openings 2l in thesleeve 2| and through the lter unit to the interior from which it passesnormally through passages I 8a to the outlet or discharge 21. The mainchamber 28 receives and holds the oil after it has passed through thelubricating system.

Chamber 29 is in communication With the interior passages I8a of thefilter and through them with the outlet 21. Partition I9 also serves asa seal between chambers 26 and 29. A pipe 35 has an opening 3D' in thechamber 26 and a discharge opening surrounded by avvalve seat 30 in thepartition I 9. A spring pressed valve 3l closes this discharge outletunder normal conditions but in case the filter becomes clogged excesspressure is built up in the chamber 26 and valve 3l is openedautomatically so that the oil from the chamber 26 may pass into thechamber 29 and back through the passages ISa inside the filter and thusthrough the discharge port 21 so that the oil feed will not be stopped.

The housing 22 is provided with an oil inlet 32 and oil outlet 33. Theinlet receives ltered oil from the chamber 29 and the outlet 33 permitsthe oil which has done the work in the motor to escape into the chamber28 through the passage 33' in the head extension 23 and sleeve 2I.

The motor has a cylinder 35 which may be cast as a part of cover plate24. In this cylinder there is a piston 36 which is moved back and forthby the pressure of the oil. Inside the cylinder is a chamber 31 whichreceives oil on one side of the piston. The chamber 25 which containsall of the valve and motor mechanism is also filled with oil. The'pistonis moved back and forth by the pressure of the oil as will be laterunderstood. In the bottom of chamber 25 is located the clutch mechanismincluding a clutch disk 4I1 which has Rods 20, 20 are secured a hollowhub 4I in the end of which the shaft I1 ts. A pin 4I' extends through aslot in the end of the shaft I1 and connects the shaft rotatably to thehub but permits longitudinal separation. A spring 42 exerts pressure tohold the shaft against longitudinal movement, the thrust of the spring42 on the shaft being transmitted by the rotatable plates to the thrustbearing provided by stationary plate I8. 'This spring pressed slidablecoupling between clutch 40 and shaft I1 is adapted to accommodate slightvariations in the length of the filtering unit and also creates aconstant one way pressure which prevents end play between the unit andits bearings. End play at these points is liable to be very destructivewhen the parts are subject to the severe vibration frequently present inaeroplane engines. A bushing 43 is preferably provided as an outerbearing for the hub 4I of the clutch disk. A bottom plate 44 serves as abearing for the clutch disk and to prevent rollers 46 wearing the metalof the housing 22. A clutch ring 45 surrounds the disk 40. Between thedisk and the ring are interposed a number of spring pressed balls orrollers 46 so that as the ring is oscillated the disk is rotated step bystep in one direction.

Between the piston of the motor and the clutch ring is a vsort of bellcrank connection. A post 41 is carried by the cover 24 and has a stepbearing 41 in the bottom of the housing 22. On this post is mounted asleeve 48 having at one end a forked arm 48 which loosely embraces aprojection 45' on the clutch ring. On the other end of the sleeve 48 isanother forked arm 48 which loosely engages the roller or pin 49 carriedby the piston. The reciprocation of the piston rocks the sleeve 48 backand forth and thus oscillates the clutch ring 45 and turns the disk 46and connected filter shaft I1 intermittently. 4

The shaft I1 may also be turned by hand. For this -purpose a gear 52 issecured to the outer surface of the clutch disc 40 and a shaft 53 ismounted in the housing and carries a pinion 54 meshing with the gear 52.One end of this shaft y53 projects through the ,cover and thus providesmeans for turning the gear 52 and the attached clutch disc by forceapplied from outside the housing. A hardened bearing member 35h may beprovided to take up the thrust of the gear 52 produced by the action ofthe spring 42. The shaft 53 is provided with a bearing in the transversewall of the housing 22 and also with another bearing in the bushing 55which is secured to cover 24 and through which one end of the shaftprotrudes. Bushing 55 has an external thread adapted to receive one endof the special nut 56 which, when in the position shown in Fig. 4,serves to protect the protruding end of the shaft and also to sealbushing 55 against oil leakage through the bearing from chamber 25. Whenit is desired to turn the filter by hand the nut 56 is unscrewed fromthe bushing and turned end for end so that seat 56' may be screwed on toshaft extension 53'; when screwed on to the shaft the nut 56 serves as ahandle or to accommodate a Wrench and by this means the filtering unitmay be rotated, in one direction, by hand. After turning the filter bymeans of the nut, the nut is readily removed by unscrewing, rotativemovement in the direction reverse to normal causing the clutch parts tolock and permitting the nut to unscrew without difculty.

The valve for controlling the action of the piston of the motor ismounted in a block 60 plunger device connected to the rocker.

let

which .is .detachably secured to the ...cover rby 'screwsf' andfrwithinthe housing. This'valve and sealing oi the -ends which are not used i.e. plugs 6| and 62 seal off the outer 'ends of these passages. 'Asmalltube 8| leads to the inlet 6| anda small tube 62 leads from theout- These tubes arecarried bythe block 68 vand are thus mechanicallysupported by the cover 24. When the parts are/assembled `as shown inFig. l0, the tube 6| extendsinto the inlet passage 32 in the housing andthe tube .62 extends into the outlet passage 33 in the housing. In theblock 68 is mounted a valve `bushing 63 which has a central cylindricalrecess in which the valve member 68 oscillates. The central part of themember B4 divides the valve chamber into two parts 63a and 63h. Thevalveblock has a passage 65 which is connected at one end to the valvechamber 63a and at the other end to a port 35a. in the cylinder 35. Asecond passage 86 in the valve block leads from theA valve chamber @3bto the chamber 25 in the housing 22.

The valve member 64 is secured to an `oscillating arm 61 which restsagainst an end surface of the bushing 83 or block 60 and has twoprojections 81 which limit the oscillatory movement of the arm 81 andattached valve. In this instance, these projections project on oppositesides of the tube 62' which serves as a stop. This arm 61 is rocked backandforth by the action of the piston 36 through a lost motion togglemechanism.

A cross bar 1|) is mounted in a slot in the piston and has a key holeslot 1| interlocked with the pin 49 which is grooved where it engagesthe bar 18. This cross bar 10 has a flange 18 which is secured to thepiston. A spacer 1li" is secured to the cross bar 18 to assist inpositioning it in the slot in the piston. This spacer 1i!" and cross bar18 also engage a slot 35 in the walls ofthe cylinder 35, as shown inFig. 6, to prevent rotation of the piston '36. A throwing leveror'rocker 12 has a shaft 12 mounted in a bushing 13 which is carried bythe plate 14, the latter plate being suitably supported lfrom. the valveblock 60. The cross bar 18 has a projection 10a which as the piston ismoved back and forth alternately engages the lugs 12a and 12b on thelever 12 so as torock the member 12 back and forth as the piston movesback and' forth. Member 12 alsoV has lugs 120 and 12d which alternatelyengage the projection 61a. on the valve arm E51 so'that-as the rocker 12is snapped back and `forth it will alternately move the valve arm61backand forth-so as to turn the valve 64 back and forth .from the positionof Fig. 5 to the position of Fig. 12 and vice versa. A spring pressedI,ball 15 engages the tip of the projection .6111.. sc as to resilientlyhold the valve arm 61y in its two respective positions.

In order to provide for the lost motion action of the rocker 12, weprovide 'a spring pressed This device comprises a pin 80 having a`flange 80' and an end part 8U" which is a slip t in pivot member 11carried invalve block 68. A tube 8| is a sliding t on pin 80 and has ahinge yconiwith;1.a:ho1e.18" in .anend wall which is1aslip .fit onrl'andisiI held againstflange 8|'. The in- .terioriof sleeve 18accommodatesone end of compression spring 19 which is a sliding rit on8|. Dash pot cylinder 16 has an extension sleeve 16" -with an end wallhaving a hole which `is a slip 't along pin 80 as far as flange l88. Theinterior fsleevel" is a sliding iit for the other end ofispringlwhichiis placed on8l and between the 1 end Yflanges of 18 and 16so that these latter enclose the spring and are urged apart by it and"transmit the spring stress through 8|] and 8| to pivot 11 andhinge 82.Dash pot piston 18 is a sliding t in cylinder 16 which has a bleed hole16"'rand relief openings 16', the bleed hole a1- lowing communicationbetween the interior of xcylinder'lii and chamber 25 at al1 times andthe relief slots, which are much larger than the `bleed, hole,duplicating thiscommunication only when the piston 18 is near theoutward end of 'its stroke and one of throwing lever lugs 12C and 12d isabout to contact oscillating arm pro- A jectionlm By this means bleedhole 16' conltrols the rate of extension of spring 19 and 'through thisgoverns the time of the operating cycle 'but .thefrelief openingsperiodically relieve the bleed control and allow the'iull power ofspring 19 to .become eiectivefor moving the valve 64 from one positionto another. This 'method'of control also'prevents destructive ham-:mer-like blows being imposed on the valve gear lby lever '12 as wouldbe the case if the spring action were not damped. The distance betweenthe lugs 12a. and 12b is such that the rocker 12 is thrown over center ashort distance before pis- Yten 36 attains its furthest in vor outposition so that if there, is a tendency for the rocker to stick,

:it can be carried furtherover center than would `in Fig. :5,vk the oilpressure created by the usual oil' pump (not shown) forces oil throughthe rfilter unit and throughthe discharge outlet 21.

Some of the oil from the chamber within the '45 kiilter unit passesthrough the inlet passage 32 (Fig. 1'0), the tube' 6|', inlet passage6I, and

" around 'the valve member 64 (Fig. 5) to the with it andthe projectionv18a. engages the lug 12ms-oas `to` turn the rocker 12 clock-wise asviewed in Figs. '7 and 9. This movement of the vrocker 12 compressesthespring 19 inthe throwking device or toggle action member and justbeforethepiston 36 reaches the outer end of its stroke the spring 19 ofthe toggle throwing device "i suddenly swings the rocker 12 so that thelug '|20 strikes against the projection 61a and suddenly turns the valve64 from the position of Fig. 5 to the position of Fig. l2. This change'of position of the valve 64 diverts the pres` sure of` the oil to theopposite end of the piston 36, the course o'f the oil pressure now being`through the passage 6|, valve chamber 63h, passage 6B-t0 chamber 125where the oil pres- `sure is "exerted against theright hand facefAof-the piston 36 vas viewed in Fig. 5. Meanwhile the oil from the otherend of the piston 36 is exhausted through the passages 35a. and 65,

chamber 65a and discharge passage 62 as previously described.

lIt will be seen from the foregoing that this construction is free fromprojecting or external moving parts or connections and that the onlyforce required to operate the filter unit under normal conditions is theengine lubricating oil pressure. It will also be seen that the powerunit is self-starting even though it has previously been stopped by suchconditions as lack of pressure or exceedingly low temperatures 0rexcessively high pressures. Although the motor has the advantage ofsimplicity of single cylinder motors there is no possibility of theparts being caught on a dead center. The oil used as a motive power istaken from the discharge side of the lter and is therefore clean andunlikely to clog up the hydraulic motor. After the oil -passes from themotor it is discharged to the engine crank case at approximatelyatmospheric pressure. located entirely within the filter unit. It shouldbe understood however that the particular elements of the device may beemployed with either external or internal connections.

As all the moving parts are immersed in the working fluid, no glands orstufng boxes are required. Also the clutch hub 4| being mounted in long,close fitting bearings, there is little likelihood of leakage.

When the cover of the housing is removed, it will be noted that allparts of the motor device come away with it so that they may be handledas a unit, and that the complete clutch mechanism can be withdrawn fromengagement with the shaft Il without the use of tools.

The motive device herein shown and described will operate on oilpressures varying from-a few pounds to more than a hundred pounds persquare inch. Pressures varying from 60 to 75 pounds are usual. Onlyapproximately 50 cubic inches per minute are required for operation.

It should be understood that various changes in details of the valvemechanism and in the other parts of the motor may be made within thescope of our invention as set forth in the following claims.

We claim:

1. A motor for a lter comprising a housing having inlet and outletpassages, a detachable cover .for said housing, a liquid actuated motorenclosed within the housing and carried by the inner side of said coverand removable therewith and including a control valve and ducts leadingto said valve carried by the cover and detachably engaged with the inletand outlet passages of the housing when the cover is applied to thehousing.

2. Motor mechanism for a lter or the like comprising a housing having aremovable cover, a motor cylinder secured to said cover within thehousing, a piston reciprocable in said cylinder, means including anoscillating valve within the housing and having passages leading to theopposite ends of the cylinder, means connected to the piston foractuating said valve, and a spring pressed toggle arm having a lostmotion connection with the valve within the housing.

3. Motor mechanism actuated by liquid pressure and comprising a housinghaving an inlet for liquid under pressure and an outlet, a cylin- In thepresent design, all passages are containingA the moving parts immersedin oil and having means at one end for connection with a support and ashaft connection for a device to be ldriven by the motor outside of thehousing, a.

clutch in the housing connected to the shaft connection, an oil pressureactuated piston in the housing, a rock shaft, means connecting the rockshaft to the piston and other means connecting the rock shaft to theclutch, means including a valve controlling passages leading to theopposite ends of the piston and passages leading to and from the housingand lost-motion means of connection between the piston and said valveall operating in the oil within the housing and a cover for the housing.

5. A liquid pressure-actuated motor comprising a housing, areciprocating liquid-pressure-actuated piston in the housing, meansincluding an oscillating Valve having passages leading to opposite endsof the piston in the housing, a spring pressed toggle device having alost motion connection with said valve, a detent coacting with saidValve and means of connection between said piston and said toggle devicefor actuating the same, all of the movable parts being immersed in theliquid in said housing, vand means of connection between said piston andan element outside of said housing.

6. In a lter moto-r, a housing, a clutch therein, a detachable cover forsaid housing, a motor cylinder and piston carried by said cover, a rockshaft supported by the housing and by the cover, one end of said shaftbeing connected to the piston and the other end of said rock shaft beingconnected detachably with a part of the clutch and a control valve inthe housing connected to the piston in the housing.

7. In a liquid-pressure-actuated motor construction, a housing, laclutch disk mounted in the housing and having a connection for anoutside shaft, a clutch ring surrounding the disk, a liquid-pressureactuated piston mounted in the housing and having means of connectionwith the clutch ring, valve mechanism mounted in the housing and havingmeans of connection with the piston, a gear member connected to theclutch disk, a pinion meshing with the said gear and means for actuatingsaid gear independently of the piston,

8. A lter motor head having an oil inlet and an outlet, a clutchImounted in oil in the head, a double acting piston in the oil in thehead, a bell crank connection between the piston and the clutch, meansincluding a valve with passages for controlling the passage of oilalternately to the opposite sides of the piston and a toggle actionthrow-over device for controlling the action of the valve.

9. In a motor, a housing, `a drive shaft extending from the housing, aremovable cover for said housing, a liquid driven piston in said coverfor actuating said shaft, a valve carried by said cover for controllingthe inlet and outlet to said piston and valve actuating mechanismcarried by said cover and operatively connected to said piston.

10. A self-starting motor comprising a housing, a removable covertherefor, a liquid driven piston in the housing for driving a shaft, avalve for controlling the inlet and outlet of liquid to said piston andmechanism operatively connected to said piston for actuating said valve,said mechanism including a toggle action device and a spring presseddash pot, said piston, valve and valve actuating mechanism beingremovable with said cover vas a unit.

11. For use in an oil driven motor system, a motor housing to be fedfrom a source of oil under pressure and to discharge oil under lesspressure back into the system, a cylinder removably mounted in thehousing, a piston reciprocable in said cylinder under pressure of saidoil, a valve device in said housing, lost motion l oil pressure to oneface of the piston and then to the other and simultaneously allowdischarge of the oil which has completed its work and means fortransmitting motion from said piston to the outside of said housing,said cylinder and piston being removable as a unit independently of saidmeans for transmitting motion to the outside of said housing.

12. For use in an oil driven motor system, a motor housing to be fedfrom a source of oil under pressure and to .discharge oil under lesspressure back into the system, a piston reciprocable in said housingunder pressure of said oil, a valve device including a valve seat and amovable valve in said housing, lost motion snap action mechanism in theoil in said housing actuated iby the movement of said piston back andforth in the housing and connected to said Avalve to alternately admitoil pressure to one face of the piston and then to the other andsimultaneously allow discharge of the oil which has completed its workand means including a clutch running in oil in said housing fortransmitting motion from said piston outside of said housing, said Valvedevice and said snap action mechanism being removable as a unit fromsaid housing.

13. An oil pressure motor including a cylinder,

" a double acting reciprocating piston therein,

valve mechanism governing the flow of oil to and exhaust from each sideof the piston, a valve operating device between said piston and valveand a housing constituting at least a portion of the wall of saidcylinder and containing said valve mechanism and said valve operatingdevice, and a piston motion translating device havsure within thehousing, said motor requiring only a small volume of oil for operationand returning the used oil to the source and having a connection in oneend of the housing for transmitting motion outside of the housing, saidinlet and said outlet being located in the same end of the housing.

15.. A self starting oil driven motor for an internal combustion enginelubricating oil lter comprising a housing having a removable cover andan extension for carrying the lter and its cleaning mechanism and forfitting within a recess in the engine wall, said housing having oilinlet and outlet passages in said extensionl and containing a pistonactuated by the pressure of oil from the engine lubricatingr system anddischarging the used oil back to the engine oil chamber, clutchmechanism in said housing actuated intermittently by said piston and ashaft connected to said clutch mechanism and extending through saidextension to drive a part of lter cleaning mechanism.

16. A self starting liquid driven motor comprising a casing having inletand outlet passages, snap action Valve mechanism for controlling saidpassages, a motor cylinder and coacting piston mounted within thecasing, said piston being actuated by liquid passing through saidpassages, means of connection between said piston and said valvemechanism, means for transmitting motion from said piston to a pointoutside of one face of said casing, and means accessible outside ofanother face of said casing for manually moving a part of said means fortransmitting motion, said means for4 manually moving a part of saidmeans for transmitting motion to a point outside of said casing beingremovable independently of the said means for transmitting motion.

17. In a liquid driven motor, a casing having a chamber With a removablecover, a driven shaft having a bearing in the bottom of the casing, aslow motion clutch mounted in the bottom of the casing and having onepart connected to said shaft, a piston reciprocable in the casing, means`of connection between said piston and another part of the clutch, and aspring-pressed snap-action valve having a lost motion connection withsaid piston, said casing having inlet and outlet passages controlled bysaid valve, said piston being removable from the casing independently ofsaid clutch.

18. A self starting liquid driven motor comprising a casing having inletand outlet passages, clutch mechanism mounted in the bottom of thecasing, a motor removably mounted in the casing and including a cylindercontaining a piston, the cylinder having a chamber at one end betweenthe piston and the adjacent end of the cylinder and the casing having achamber between the piston and inner walls of the casing, valvecontrolled means having passages connecting the inlet and outletpassages with the respective chambers, means of connection between thepiston and the clutch mechanism for actuating the clutch mechanism fromthe piston, and means of connection between the piston and the valvewhereby the valve is actuated by the piston.

PHILIP E. ASHTON. SIDNEY L. WOLFSON.

